Stent-Assisted Coiling of Intracranial Aneurysms: Predictors of Complications, Recanalization, and Outcome in 508 Cases

Background and Purpose— Self-expanding stents are increasingly used for treatment of complex intracranial aneurysms. We assess the safety and the efficacy of intracranial stenting and determine predictors of treatment outcomes. Methods— A total of 508 patients with 552 aneurysms were treated with Neuroform and Enterprise stents between 2006 and 2011 at our institution. A multivariate analysis was conducted to identify predictors of complications, recanalization, and outcome. Results— Of 508 patients, 461 (91%) were treated electively and 47 (9%) in the setting of subarachnoid hemorrhage. Complications occurred in 6.8% of patients. In multivariate analysis, subarachnoid hemorrhage, delivery of coils before stent placement, and carotid terminus/middle cerebral artery aneurysm locations were independent predictors of procedural complications. Angiographic follow-up was available for 87% of patients at a mean of 26 months. The rates of recanalization and retreatment were, respectively, 12% and 6.4%. Older age, previously coiled aneurysms, larger aneurysms, incompletely occluded aneurysms, Neuroform stent, and aneurysm location were predictors of recanalization. Favorable outcomes were seen in 99% of elective patients and 51% of subarachnoid hemorrhage patients. Patient age, ruptured aneurysms, and procedural complications were predictors of outcome. Conclusions— Stent-assisted coiling of intracranial aneurysms is safe, effective, and provides durable aneurysm closure. Higher complication rates and worse outcomes are associated with treatment of ruptured aneurysms. Stent delivery before coil deployment reduces the risk of procedural complications. Staging the procedure may not improve procedural safety. Closed-cell stents are associated with significantly lower recanalization rates.